Recherche avancée

Sur d’autres sites (7859)

• Rendering video by ffmpeg.wasm in browser occured an error

  15 septembre 2022, par James Bor

  When a local video renderer uses the ffmpeg.wasm library in the Chrome browser, very often an error with the SBOX_FATAL_MEMORY_EXCEEDED code occurs during the rendering process. The standard command set is used. The code below is half fake because it is very long, but describes an approximate action algorithm. Computer performance and RAM capacity do not affect the video, files used - minimal size. Has anyone experienced this and how can we solve it ?
Error screen

  


  const videoGenerate = async (project) => {
  const ffmpeg = createFFmpeg({
      corePath: 'ffmpeg/ffmpeg-core.js',
      workerPath: 'ffmpeg/ffmpeg-core.worker.js'
  });
  await loadFfmpeg(ffmpeg);
  project.projectName = "Default";
  project.fileType = "video/mp4";

  const resultVideo = {
    title: `${project.projectName}ConcatenatedVideo.mp4`,
  };
  // *For fetchFile method and ffmpeg.FS('writeFile', title, file);
  await uploadObjects(project.projectName, ffmpeg);
  // *
  const command = ['-i', project.video, resultVideo.title];
  await ffmpeg.run(...command);
  await ffmpeg.FS("unlink", resultVideo.title);
  resultVideo["blob"] = ffmpeg.FS('readFile', title);
  return resultVideo.blob;
};


  


  These dependencies are used : "@ffmpeg/core" : " 0.8.5", "@ffmpeg/ffmpeg" : " 0.9.7". Upgrading the library to the latest version does not work either.

  


• How to use the result of guardian-ffmpeg-Android ?

  4 avril 2013, par user1914692

  I am trying to build ffmpeg on Android. There are many tutorials. Some are very old.
  So I want to try one that can use newer version of ffmpeg and Android NDK.
  After long time searching, I find one, guardianproject / android-ffmpeg

  The project was updated several months ago.
  NDK r8 is used. ffmpeg is put from online, so a latest version.

  After I follow all the instruction, I am confused which result I should use, and how to use it.
  The README mentions testing, like :

  # embedding metadata into a matroska video /data/local/ffmpeg -y -i test.mp4 \
  
      -attach attach.txt -metadata:s:2 mimetype=text/plain \
  
      -acodec copy -vcodec copy testattach.mkv

  First, I fail to find the path : /data/local
  Second, this is a command. How will I use it in Android ?

  Totall confused.
  Any light ?

• FFMPEG - What are some recommended parameters for x265 (libx265) ?

  7 janvier 2019, par dd_code

  I am working on re-encoding some footage (x264), including some grainy footage. I am interested in CRF-only bitrate management (I want to avoid artifacts during demanding scenes).
  What are recommended parameters to be set instead of leaving them at their defaults ?

  Here is what I got so far, pretty simple :

  ffmpeg -i in.mkv -vf unsharp=3:3:1 -c:v libx265 -tune:v grain -crf 24 -c:a copy out.mkv

  (this example has grain tune as many files are grainy, and without it it washes it out and all the "detail by noise" is lost + I am applying a light sharpening filter, I find there is always a room to sharpen a bit without causing noticeable sharpening artifacts)

  If I am not mistaken all the params one does consider are ones contained in the presets, but is there some other or one of those which is a good practice to adjust manually to achieve a better result ? I was wondering specifically about P,I,B-frames and AQ (but I guess there are some other as well).